Sensor tape for security detection and method of fabrication

ABSTRACT

A sensor in the form of an elongated flexible tape has a plurality of signal paths made from electrical wire or optical fiber which extend between one end and another end of the tape. The electrical wires or optical fibers are disposed in spaced relation across the width and along the length of the tape, and are terminated in connectors at the endpoints of the tape. One connector includes a multiplexer to which an input signal is applied for propagation along the signal paths, The other connector includes an AND gate which provides an output signal which changes in the event of a break in any one or more of the signal paths, thereby indicating an alarm condition. The connectors may be integrated into a signal detector to interface with communication links. The tape is a material that is non-conductive and in which the wires or optical fibers may be woven, disposed or embedded in some manner.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of U.S. patent applicationSer. No. 13/440,376 filed Apr. 5, 2012 entitled “Sensor Tape forSecurity Detection and Method of Fabrication” which claims the benefitunder 35 U.S.C. §119(e) of U.S. Provisional Patent Application No.61/590,589, entitled “3 Dimensional Fuse And Method Of Fabrication,”filed on Jan. 25, 2012, which is herein incorporated by reference in itsentirety for all purposes.

This application is related to a number of issued patents and pendingpatent applications, in the name of the inventor of the presentapplication, that relate to tamper proof containers and other enclosuresand security systems for containers, enclosures, pipelines and otherstructures. The issued U.S. patents are: U.S. Pat. Nos. 7,211,783;6,995,353; 7,394,060; 7,608,812; 7,332,728; 7,098,444; 7,482,924;7,619,226; 7,856,157, 7,924,166, and 8,207,861.

BACKGROUND OF THE INVENTION

As is known, in order to detect an intrusion into, or out of, aprotected volumetric space, a sensor sheet is provided to enclose thevolume of interest which has a continuous electrical or optical signalpath disposed in the sheet and substantially encompassing the fullextent thereof. An electrical signal, in the case of a wire path, or anoptical signal, in the case of an optical fiber path, is introduced toone end of the signal path, and the signal is received at the oppositeend of the signal path. The presence of a signal indicates a normal ornon-alarm state. In the event of a break or other interruption in thesignal path, the loss or diminution of the signal is detected andsignifies an alarm condition. In the case of an optical fiber signalpath, the optical fiber can be sensitive to incident nuclear radiationthat causes a reduction in the amplitude and/or characteristics of theoptical signal and which can be detected as an indication of an alarmcondition.

Current fabrication techniques for installation of sensor sheets involvefirst applying a resin layer to the surface of the object to beenclosed, e.g., the interior walls of a cargo container or the outersurface of a pipeline. The resin must be allowed to dry to a certainpoint and then, within a specified time window, i.e., before the resinhardens, the sensor sheet is to be laid on top. A top layer of resin isthereafter applied and allowed to dry to hold fast the sensor sheet in aprotective sandwich construction.

In some applications, for example, gas wells, it is not as much of anissue of security but, rather, one of locating a failure in order toquickly make a repair. Gas wells usually include a pipeline casing,however, when the casing is compromised and gas escapes through theground to the surface, known as “surface casing vent flow and gasmigration,” it must be repaired. The release of gas has to be stopped assoon as detected, and while it is relatively easy to detect that gas isleaking, identifying the location of the leak along the length of thecasing is a much bigger challenge.

A known detection method runs an acoustic instrument down the well thatdetects noise patterns that are plotted on a graph as the instrument isslowly withdrawn. Any variances of sound, such as pitch, will be used toidentify the location of the leak. When a leak location has beendetermined, a hole is made in the casing and cement is inserted in tostop the gas leak. The instrument, however, must be run again to assurethat the hole has been plugged but a relatively large retry rate isnecessary to finally seal the leak. The delays associated with thisprocess of determining where the leak is located translate into lostoperating time, the incurring of repair costs and, therefore, decreasedrevenue for the gas well operator.

There is, therefore, a need for providing a mechanism that will detectan intrusion or extrusion with respect to a pipeline container orenclosure and that can be applied quickly, easily and economically andthat will be able to provide detection coverage for irregularly as wellas regularly shaped volumetric enclosed structures. Additionally,determining a location of a defect is also needed in order to apply arepair.

BRIEF SUMMARY OF THE INVENTION

In one embodiment, a sensor security detector tape includes a materialstrip with predetermined width and length and first and second ends. Atleast one signal path is provided in the material strip where eachsignal path has a first end and a second end. First and secondconnectors are coupled to the first and second ends, respectively, ofthe signal paths.

In another embodiment, a method of fabricating a sensor securitydetector tape includes providing a material strip having a predeterminedwidth and a predetermined length and first and second ends and couplingat least one signal path to the material strip, where each at least onesignal path has a first end and a second and. Subsequently, first andsecond connectors are coupled to the first and second ends,respectively, of the signal paths.

The signal paths may be either wire or optical fiber.

In another embodiment of the invention, a plurality of conductive pathsare connected at one end to a multiplexing circuit to which an inputsignal is applied for propagation along all of the conductive paths. Theother end of the plurality of conductive paths is connected to a logicalcircuit which provides an output signal. A break in any one of theplurality of conductive paths will cause a loss of conduction in thebroken paths and a change in the output signal from the logical circuit.The logical circuit in one implementation is an AND gate. The gateoutput is in one state when all of the conductive paths are intact andcarrying a signal. The output of the gate will change state in theabsence of conduction in any one or more of the paths. This change ofstate is indicative of an alarm condition.

The logical circuit can be of other forms known to those of skill in theart to provide the intended function. The multiplexer and the AND gateor other logical circuit can be housed within respective connectors towhich the plurality of signal paths are coupled.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Various aspects of at least one embodiment of the present invention arediscussed below with reference to the accompanying figures. It will beappreciated that for simplicity and clarity of illustration, elementsshown in the drawings have not necessarily been drawn accurately or toscale. For example, the dimensions of some of the elements may beexaggerated relative to other elements for clarity or several physicalcomponents may be included in one functional block or element. Further,where considered appropriate, reference numerals may be repeated amongthe drawings to indicate corresponding or analogous elements. Forpurposes of clarity, not every component may be labeled in everydrawing. The figures are provided for the purposes of illustration andexplanation and are not intended as a definition of the limits of theinvention. In the figures:

FIG. 1 is a schematic representation of a sensor tape structure inaccordance with an embodiment of the present invention;

FIG. 2 is a schematic representation of a sensor tape structure inaccordance with another embodiment of the present invention;

FIGS. 3A and 3B are electrical schematic representations of the sensortape structures of FIGS. 1 and 2;

FIG. 4 is an exploded view of a sensor tape structure in accordance withan embodiment of the present invention;

FIGS. 5A and 5B are representations of applications of an embodiment ofthe sensor tape structure in accordance with the present invention;

FIG. 6 is a block diagram of an intrusion/extrusion detection system inaccordance with an embodiment of the present invention;

FIG. 7 is a block diagram of an intrusion/extrusion detection system inaccordance with an embodiment of the present invention;

FIG. 8 is a block diagram of an intrusion/extrusion detection system inaccordance with an embodiment of the present invention;

FIG. 9 is a representation of a spool of sensor tape in accordance withan embodiment of the present invention;

FIG. 10 is a block diagram of a system in accordance with an embodimentof the present invention;

FIGS. 11A and 11B are representations of a sensor tape in accordancewith an embodiment of the present invention;

FIGS. 12A and 12B are representations of a sensor tape in accordancewith an embodiment of the present invention;

FIGS. 13 and 14 are alternate arrangements of a signal path in a sensortape in accordance with embodiments of the present invention;

FIG. 15 is an application of a sensor tape in accordance with anembodiment of the present invention;

FIG. 16 is an application of a sensor tape in accordance with anembodiment of the present invention; and

FIG. 17 is a schematic representation of another embodiment of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

This application is a continuation in part of U.S. patent applicationSer. No. 13/440,376 filed Apr. 5, 2012 entitled “Sensor Tape forSecurity Detection and Method of Fabrication” which claims the benefitunder 35 U.S.C. §119(e) of U.S. Provisional Patent Application No.61/590,589, entitled “3 Dimensional Fuse And Method Of Fabrication,”filed on Jan. 25, 2012, which is herein incorporated by reference in itsentirety for all purposes.

Further, each of U.S. Pat. Nos. 7,211,783; 6,995,353; 7,394,060;7,608,812; 7,332,728; 7,098,444; 7,482,924; 7,619,226; 7,856,157 and7,924,166 is incorporated by reference herein in its entirety for allpurposes.

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of the embodiments ofthe present invention. It will be understood by those of ordinary skillin the art that these embodiments of the present invention may bepracticed without some of these specific details. In other instances,well-known methods, procedures, components and structures may not havebeen described in detail so as not to obscure the embodiments of thepresent invention.

Prior to explaining at least one embodiment of the present invention indetail, it is to be understood that the invention is not limited in itsapplication to the details of construction and the arrangement of thecomponents set forth in the following description or illustrated in thedrawings. The invention is capable of other embodiments or of beingpracticed or carried out in various ways. Also, it is to be understoodthat the phraseology and terminology employed herein are for the purposeof description and should not be regarded as limiting.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable sub-combination.

Embodiments of the present invention relate to a an elongated flexiblesensor security detector tape having a signal path provided therein byelectrical wire or optical fiber and which extends between one end ofthe tape to the other end of the tape. In one embodiment, as will bedescribed in more detail below, a plurality of electrical wires oroptical fibers are disposed in the tape in a spaced relation, e.g.,parallel to one another, across the width of the tape and extendingalong the length of the tape. The tape may include a non-conductivematerial in which the wires or optical fibers are woven or otherwisedisposed in, for example, a polyester material. Protective layers offlexible material may be laminated on respective sides of the sensortape to provide a laminated structure that is robust and that can bereadily rolled and unrolled from a reel for efficiency of transport andfor installation on a structure to be protected, e.g., by encapsulatingany configuration of volumetric space, such as a pipeline, byspin-wrapping. Spin-wrapping is a well understood technique in thepipeline industry used to apply an insulation material to pipes in orderto provide a solid coating, for example, a thermal-protecting coating.

Additionally, after application by spin-wrapping, a protective resincoating can be applied over the sensor tape segments as an additionalprotective layer. Tuffset P resin, available from Isothane Ltd. in theUnited Kingdom, is one such resin available for this application.

In one embodiment of the present invention, a linear sensor tape segment100 includes a material strip 104. A plurality of signal paths 108.n aredisposed either on, or within, the material strip 104, as shown inFIG. 1. The signal paths 108.n may comprise electrical wires forcarrying an electrical signal or optical fibers for carrying an opticalsignal. In one embodiment, the material strip 104 may be, but is notlimited to, a non-conductive fabric material in which the wires oroptical fibers may be woven or otherwise disposed. Here, the pluralityof signal paths 108.n are spaced across the width of the material strip104, generally parallel to one another, but not electrically oroptically coupled to one another. The electrical wires may or may not beindividually insulated. The resolution distance between the signal paths108.n in the material strip 104 can be chosen as needed and, in oneembodiment, is approximately 0.25 inches, although almost any distanceas will fit the requirements can be chosen. The length of the linearsensor tape segment 100 may be cut to fit the particular application.Once cut to the desired length, two bridging connectors 112.1, 112.2 arecoupled, respectively, to the ends of the material strip 104. Thefunction of the bridging connectors 112.1, 112.2 will be describedbelow.

In another embodiment of the present invention, as shown in FIG. 2, asinuous sensor tape segment 200 includes the material strip 104 with asole signal path 108 comprising an electrical wire or an optical fiber.Here, the sole signal path 108 is distributed in a sinuous patternacross the width of the material strip 104. Two terminating connectors204.1, 204.2 are coupled, respectively, to the ends of the materialstrip 104. The function of the terminating connectors 204.1, 204.2 willbe described below.

Referring now to FIG. 3A, each bridging connector 112.n includes aplurality of jumper links 304 to electrically, or optically, couple thesignal paths 108.n into a single continuous signal path, as representedby the arrows. The bridging connector 112 is provided at the end of eachlinear sensor tape segment 100 to bridge, i.e., interconnect, the signalpaths 108.n, i.e., the wires or optical fibers in the linear sensor tapesegment 100 to provide a single continuous signal path through thelinear sensor tape segment 100 from one end to the other. The jumperlinks 304 are arranged to correspond with the signal paths 108.n and thebridging connector 112 would be sized to match the width of the fabric104. The bridging connector 112 also includes a pass-through link 308that couples the single continuous signal path either to a signalsource, a next sensor tape segment or a signal sensing system.

The terminating connector 204 includes a pass-through link 308, as shownin FIG. 3B, to provide an interface to the sole signal path 108. Ofcourse, the terminating connector 204 is sized to match the materialstrip 104 and couple to the corresponding end of the sole signal path108.

The connectors 112, 204 may be Flexible Printed Circuit (FPC) typeconnectors as available from many different vendors such as Tyco orMolex. As known to one of ordinary skill in the art, an FPC typeconnector will clamp onto the sensor tape segment and couple to thesignal paths.

A number of protective layers 404, 408 of a flexible material may belaminated on respective sides of either of the sensor tape segments 100,200 to provide a laminated structure, as shown in FIG. 4 (in explodedview). Here, the signal path 108 is shown as being provided within thematerial strip 104 merely for ease of explanation although otherembodiments as described herein are also applicable. The protectivelayer or layers 404, 408 are provided to protect the inner sensor tapesegment 100, 200. The one or more protective layers 404, 408 of suitablematerial can be laminated or otherwise secured to each side of thesensor tape segment 100, 200 with the properties needed to suit aparticular installation's requirements.

The protective layers 404, 408 may be, for example, silicone rubber orplastic and may be attached to respective sides of the sensor tapesegment 100, 200 by any one of a number of mechanisms, including, butnot limited to, gluing with an adhesive, heat bonding, pressure bonding,etc. The protective layers 404, 408 may be waterproof and resistant toother environmental and other contaminants to which they may be exposed.The protective layers may also have releasable layers of paper to bepeeled off prior to application.

In one embodiment, an adhesive outer surface 412 may be provided toallow for initial bonding to the surface of, for example, a pipe, duringinstallation of the tape, where the surface may or may not have a sheenlayer of anti-corrosion film already applied.

One of skill in the art will understand that the number of protectivelayers 404, 408 may vary depending upon the needs of the application.Further, various combinations and sub-combinations of the protectivelayers 404, 408 in conjunction with the adhesive layer 412 arecontemplated, for example, where the adhesive layer 412 is applied tothe sensor tape 100, 200 without there being a protective layer 408disposed between. In addition, a sensor tape 100, 200 may be“sandwiched” between two adhesive layers 412, with or without,protective layers on either side. Still further, a structure withmultiple layers of sensor tape 100, 200 is also contemplated as beingwithin the scope of this invention.

The sensor tape segment 100, 200 is fabricated in lengths suitable forspin wrapping or other application onto an enclosure or protected space.In one embodiment, the tape segment 100, 200 is about 5-7 inches wideand about 250-300 feet long. The sensor tape 100, 200, with or withoutprotective layers 404, 408, or an adhesive layer 412, may be provided ona spool 904, as shown in FIG. 9. Of course, one of ordinary skill willunderstand that any necessary release layers would be provided in orderto allow for the unrolling of the sensor tape 100, 200 when beingapplied, as described below.

In one application, the sensor tape segments 100, 200 are wrappedaround, for example, a pipeline or pipe section 504, as shown in FIG.5A, to provide an effectively continuous wrapping. The sensor tapesegments 100, 200 may be helically wrapped around the pipe section 504.The connectors 112, 204 of sequentially adjacent sensor tape segments100, 200 are interconnected to provide a continuous signal path throughthe multiple tape segments. The wrapping can be guided on the irregularsurface of a pipe by sensors to ensure edge-to-edge alignment of thetape to ensure a smooth continuous wrap. For example, a stripe or markercan be placed along the longitudinal edge of the tape and can bevisually, by person or machine, monitored to align the tape segments byoptical recognition and feedback as would be understood by those ofordinary skill in the art. In addition, a raised edge may be provided onthe tape segment and used as an indicator to align segments when beingapplied.

In another application, by applying a second sensor tape segment over afirst tape segment an effective resolution can be improved. Referring toFIG. 5B, for example, a first sensor tape segment 100.1 is placed, e.g.,wrapped, in a first orientation about the item and a second sensor tapesegment 100.2 is wrapped in a second orientation different from thefirst orientation, about a portion of the first sensor tape segment100.1. As a result, a portion of the plurality of parallel signal paths108 in the second sensor tape segment 100.2 cross a portion of theplurality of parallel signal paths 108 in the first sensor tape segment100.1. Thus, a grid of signal paths is established. Where the signalpaths are ¼ inch apart, if applied at right angles to one another, aneffective resolution of 1/16 square inch can be had as shown in FIG. 5B.Still further, the second tape segment 100.2 may be applied at anyangle, not just a right angle, to the first tape segment 100.1.

Thus, if each of the multiple layers is geometrically offset from theothers by a predetermined distance, the effective detection resolutionis increased, i.e., the density of wires per square area is increased.Accordingly, any desired cost-effective detection resolution can beestablished. In principle, multiple offset layers can theoreticallyreduce the aperture of resolution to such a small opening that aneffectively “solid wall” is provided that detects a breach, i.e., eitheran intrusion or extrusion, of any size.

Alternately, a single tape segment could be wrapped back on itself toeffectuate the same grid of signal paths.

The sensor tape segment 100, 200 of the present invention can be readilyinstalled in the field by spin wrapping onto pipe sections as they arebeing constructed into a pipeline. Alternatively, the sensor tapesegment 100, 200 can be factory installed on sections of the pipe beforeit is transported to an installation site. This would likely be moreeconomical for making smaller pipes such as those found in chemicalplants or nuclear plants, for example.

An overcoating of polyurethane or other suitable material can be appliedover the tape segments 100, 200 after being wrapped about the pipe 504to protect against wear, abrasion and other adverse or damagingconditions to which the pipe 504 may be exposed.

Alternate embodiments of the sensor tape will now be described. It isunderstood that the following embodiments may be implemented in themulti-layer tape described above.

Referring now to FIGS. 11A and 11B, a sensor tape segment 1100 includesa single-ply tape strip 1104 such as, for example, duct tape, havingadhesive material 1108 disposed on a surface of the single-ply tapestrip 1104. The single-ply tape strip 1104 could also be, for example, aplastic or rubber material with the adhesive material 1108 disposedthereon. One of ordinary skill in the art will understand the manymechanisms for applying the adhesive material 1108 in addition to thechoices of adhesive depending on desired tackiness, removability, etc.As shown, the parallel signal paths 108.n may be placed in the adhesivematerial 1104. A cross-section side view of the sensor tape segment 1100is shown in FIG. 11B. The single-ply tape strip 1104 can be of anydesired width.

In order to allow for rolling on a reel, to be used with a handheld ormechanized wrapping machine such as used for wrapping packing tapearound boxes, a releasable layer 1112 may be provided over the signalpaths 108.n. The releasable layer 1112 may comprise a thin flexiblesheet and adheres to the exposed adhesive material 1108 between thesignal paths 108.n. As described above, the signal paths 108.n may beinsulated or bare electrical wires or optical fibers with or withoutprotective cover. In addition, a connector 112 can be attached to eachend of the sensor tape segment 1100 for interconnecting the wires orfibers as described above.

Referring now to FIGS. 12A and 12B, a sensor tape segment 1120, similarto the sensor tape segment 1100, includes a single-ply tape strip 1104having adhesive material 1108. As shown, instead of parallel signalpaths 108.n, a sole sinuous signal path 108 may be placed in theadhesive material 1104. A cross-section side view of the sensor tapesegment 1120 is shown in FIG. 12B. Similarly to that already disclosed,a releasable layer 1112 may be provided.

There are variations on the sole signal path where, as shown in FIG. 13,a hybrid approach is used that includes parallel rows with interleavedsinuous paths. Depending upon the spacing, a single path is providedwith finer detection resolution as compared to only parallel paths oronly a sinuous path.

Still further, a meandering, i.e., randomly, or semi-randomly, arrangedsole signal path may be provided as shown in FIG. 14. Such a meander maybe chosen to provide a minimum necessary detection resolution.

Each embodiment of the present invention can be used to detect thepresence or absence of an event such as, for example, a bullet hole inthe pipeline 504 or thieves placing a “bleeder” tube into the pipeline504 (intrusion events) or a corrosion induced leak or a corrosive holeforming in the pipeline 504 and leaking fluid (extrusion events).Similarly, an intrusion into a secured cargo container or an extrusionevent, such as, radiation detection from within an enclosed space, maybe detected.

In operation, the absence of an electrical or optical signal provides aself-monitoring feature that does not require initiating an activesignal to interrogate a secured system in order to obtain a response. Afail-safe “always on” conducting signal that fails to be detected in acontinuous manner indicates a “problem,” be it the detection of anintrusion event or an extrusion event or failure of the systemcomponents such as its power supply. This detection information may beprovided and monitored in real-time to enable either the determinationof a location of an event at a specific pipe segment or the presence ofa failed component in the sensor tape segment which, in effect, shutsthe system down. Thus, a failed component is treated as an intrusion orextrusion event.

In one embodiment, an output 604.n of each respective tape segment orstrip 100, 200 is fed to a NOR gate function 608 and then to a processor612, such as shown in FIG. 6. In a normal non-alarm condition, a signalis received from each tape segment 100, 200 and is applied to theprocessor 612 to signify the normal state. If an incursion or excursionevent occurs that causes a break in the signal path 108 of even a singlewire of a tape segment 100, 200, the signal 604.n from that segment 100,200 will cease, which will cause the NOR gate function 608 to present analarm signal to the processor 612 which will produce an alarm output616. One of ordinary skill in the art will understand that the NOR gatefunction 608 may be provided by discrete components or could beperformed within the processor 612 if all output signals 604.n areprovided to the processor 612.

In another embodiment, the processor 612 can identify the tape segmentwhere the alarm event has been detected and can provide other data asmay be required or desirable. Referring now to FIG. 7, a number ofsensor tapes 100, 200 are connected in series where the output signal604.n of one is the input to the next. The output signal 604.n of eachsensor tape is also submitted to the processor 612 to be processed asdescribed above where the lack of an output signal indicates an eventand the specific sensor tape 100, 200 that has detected the event can bedetermined.

Alternately, where a number of sensor tapes 100, 200 are connected inseries, as shown in FIG. 8, a single output 604.n may be provided to theprocessor 612. If the signal on the single output 604.n ceases, theprocessor 612 will raise the alarm output 616 as detecting an eventalthough the location of the event, i.e., the specific sensor tape 100,200 that detected the event, in this particular embodiment, cannot bedetermined.

Information regarding the alarm event can be transmitted to one or morelocal and/or remote receiving sites by any wired or wireless modalityprovided in conjunction with the processor 612.

As described above, each connector 112, 204 is provided to allow asignal to be passed along any length of pipeline desired by connectingthe output electrical or optical signal from one end of a sensor tape100, 200 corresponding to an individual pipe segment to the inputconnector of the next sensor tape 100, 200 corresponding to the nextpipe segment. Alternately, each pipe segment comprising an individualunit within a pipeline system may have, in addition to connectors onboth ends, a system 950, implemented as, for example, an integratedcircuit device, which can have monitoring functions built into itsmicroprocessor platform with associated software, as shown in FIG. 10.The system 950 may be integrated into a connector 112, 204.

The device 950 may include a processor 952 and a memory 954 that canhold data identifying a respective pipe segment in the pipeline system,such as a unique pipe segment address that allows for identification ofthe specific pipe segment where a detected problem has occurred. Thedevice 950 can have a real-time clock 956 for time and date informationthat facilitates identification of the detected event. In addition, aGPS device 958 may be included to provide location information. Ofcourse, if the location is static, i.e., not moving, then a GPS devicemay not be needed and the static location information can be stored inthe memory 954. Alternatively, the device 950 can act as a node totransmit status data through any modality such as, for example,satellite, wire, wireless, and/or internet, for example, with anappropriately configured transceiver 960. The system may be powered by abattery 962 that can be charged by solar power, for example. A devicesuch as the Snapdragon™ processor available from Qualcomm Incorporatedmay be used.

Further, in the application to a pipeline, as each pipe segment isinstalled in the pipeline, a real time test of conductivity of thesensor tape 100, 200 can be instituted for each electrical wire oroptical fiber embedded in the tape strip as it is wrapped around thepipe segment. The test signal detected in this initial wrapping insuresthat any problems in connectivity are immediately detected in real-timeto optimize cost and performance functions.

Still further, embodiments of the present invention allow for testingthe integrity of an entire system and for detecting the falsification ofthe signal indicating that no incursion or excursion has been detectedbecause of the fail-safe nature of the system and its binary output(signal/no-signal). If, for example, a third party were interfering withthe output signal and had over-ridden it to always indicate a safecondition, the operator could test for this by turning off power to thesensors and determining whether or not the output of the system changesstate. Of course, either the entire system could be turned off or onlyone or more of the sensor segments. If the output signal does not changein response to all, or part, of the system being shut down, then theremay be some interference with the system in progress.

Embodiments of the present invention may also be made of materials andcomponents that are meant to reduce the cost in order to make the tapesensor either disposable or for single-use. Thus, for example, the tapemay be thinner, such as for packing applications, where removal of thetape when opening the package permanently renders the tape inoperative.In addition, the components within the connector may have lessfunctionality, in order to reduce cost, and, therefore, lend themselvesto disposable applications.

Known installations of detector sheets include a process of applying aresin and then having to wait for the resin to reach a point oftackiness for subsequent attachment of the sensor sheet. Advantageously,embodiments of the present invention simplify the fabrication andinstallation of a sensor system. As described above, the sensor tape100, 200 has silicone rubber laminated or applied on both sides andforms a multi-layer tape. In one example, this might be provided as aroll of rubberized tape with the sensor sandwiched in the middle, forexample, measuring 6 inches wide and 250 feet long to allow for use in a“spin wrap” process, well known to those in the pipeline insulationwrapping business, to rapidly encapsulate a pipe for a pipeline to beprotected by the tamper proof tape to provide for detection of anintrusion/extrusion event.

Referring now to FIG. 15, a pipe 1504, which could be a gas well casingor similarly shaped object will have a plurality ofcircumferentially-placed (CP) sensor tapes 1508.1 . . . 1508.nseparately arranged around the circumference of the pipe 1504 andadjacent one another along the pipe 1504, i.e., longitudinally arrangedand not helically positioned. The CP sensor tapes 1508.n are arranged soas to effectively cover the entire outer surface area of the pipe 1504.The CP sensor tapes 1508.n may be any one of the sensor tape typesdescribed above. A bus 1512 runs along the length of the pipe 1504 andeach CP sensor tape 1508.n is connected to the bus 1512.

In one embodiment, each CP sensor tape 1508.n receives an input signalfrom, and provides an output signal to, the bus 1504. The bus 1504 mayalso provide power and any other necessary signals to each CP sensortape 1508.n as well as be in communication with, for example, a centralmonitoring station either by wired or wireless communications protocols.Alternately, each CP sensor tape 1508 may be self-contained andsupplying only the output signal to the bus 1504.

Each CP sensor tape 1508.n is uniquely identifiable, either by a uniqueaddress value programmed into the system 950 within a connector on theCP sensor tape 1508.n or by its respective location along the bus 1512.Thus, the location of each CP sensor tape 1508.n with respect to thelength of the pipe 1504 is known.

In operation, when, for example, a rupture occurs in the wall of thepipe 1504 and gas is leaking out, the signal in a signal path of atleast one of the CP sensor tapes 1508.n will be disrupted. The loss of asignal will be detected by circuitry either on the communication bus1512, and this condition will be conveyed to the central system, or thebus 1512 will only be a conduit for the output signal, or lack thereof,to reach the central system where the determination of a lost signalwill be made. The circuitry on the bus 1512 will report the identifierof the failed sensor tape 1508.n and the central system may determinewhere the breach is located. One of ordinary skill will understand thatthere are many different bus protocols that may be implemented forconnection and communication among the bus 1512, the CP sensor tapes1508.n and the central system.

Once the reporting CP sensor tape 1508.n is identified, and its locationhas been determined, repair operations can be started. One of ordinaryskill in the art will understand that the embodiment shown in FIG. 15will identify a circular “breach band” around the pipe and at a locationalong the length of the pipe 1504 within which the breach has occurred.This “breach band” will be as wide as the CP sensor tape 1508.n.

An embodiment that identifies the location around the circumferencewithin the “breach band” will now be described with reference to FIG.16. As shown, the plurality of CP sensor tapes 1508.n are providedaround the pipe 1504, similar to that shown in FIG. 15 and each isconnected to the bus 1512 as already described.

Additionally, a plurality of longitudinally-positioned (LP) sensor tapes1520.1 . . . 1520.n are arranged around the circumference of the pipe1504 over the CP sensor tapes 1508.n. The LP sensor tapes 1520.n can beany one of the type of sensor tape described above. The LP sensor tapes1520.n are placed so as to cover the entire surface of the pipe 1504.

Alternatively, the LP sensor tapes 1520.n may be placed first with theCP sensor tapes 1508.n placed over the LP sensor tapes 1520.n.

Each LP sensor tape 1520.n is connected to the bus 1512 and receives aninput signal from, and provides an output signal to, the bus 1504. Thebus 1504 may also provide power and any other necessary signals to eachLP sensor tape 1520.n. Alternately, each LP sensor tape 1520 may beself-contained and supplying only the output signal to the bus 1504.Each LP sensor tape 1520.n is uniquely identifiable, either by a uniqueaddress value programmed into the circuitry within a connector on the LPsensor tape 1520.n or by its respective connection location to the bus1512. Thus, the location of each LP sensor tape 1520.n with respect tothe circumference of the pipe 1504 is known.

In operation, when, for example, a rupture occurs in the wall of thepipe 1504 and gas is leaking out, the signal in a signal path in a CPsensor tape 1508.n and an LP sensor tape 1520.n will be disrupted. Theloss of these two signals will be detected and the specific CP sensortape 1508.n and specific LP sensor tape 1520.n will be identified. As aresult, more precise coordinates of a breach, along the length andaround the circumference, can be determined.

If, for example, each LP sensor tape is W inches wide, then an area ofW² inches at a location along the length and around the circumference ofthe pipe 1504 has been identified as having a leak within it. This morespecific locating function allows for repair operations beingimplemented more quickly and accurately.

Another embodiment is shown in FIG. 17. A material strip 1600 has aplurality of signal paths 1602 disposed along the length of the stripfrom one end to the other, in similar manner to that shown in theembodiment of FIG. 1 herein. The signal paths may comprise electricalwires for carrying an electrical signal or optical fibers for carryingan optical signal. A multiplexer 1604 is connected to the ends of theconductive paths at a first end of the material strip 1600. An AND gate1606 is connected to the conductive paths at the second end of thematerial strip. The output of the AND gate is connected to a processor1608 which provides an output signal. In operation, a signal is appliedto the input of multiplexer 604 which provides signals on all of theconductive paths 1602. In the presence of signals on all of the inputsto AND gate 1606, the gate provides an output signal to processor 1608which in turn provides an output signal which indicates normal,non-alarm, operation. In the event of a break in any one or more of theconductive paths 1602, the absence of one or more signals on the ANDgate inputs will cause a change in the output signal of the AND gate andconsequent change in the output signal of the processor 1608 to signifyan alarm state or condition. It will be appreciated that the AND gatecan be provided as a separate logical gate or can be incorporated intothe processor 1608. It will also be appreciated that other types oflogical circuits can be employed to provide the intended function.

Embodiments of the present invention produce a fail-safe,self-monitoring, reliable, durable and robust tape/fabric sensor systemable to withstand the rigors of harsh environmental conditions such asexperienced by a pipeline or cargo container. Embodiments of the presentinvention can be utilized in both aboveground and underground pipelinesystems and can be applied as new construction in a factory or as afield installed retrofit.

Having thus described several features of at least one embodiment of thepresent invention, it is to be appreciated that various alterations,modifications, and improvements will readily occur to those skilled inthe art. Such alterations, modifications, and improvements are intendedto be part of this disclosure and are intended to be within the scope ofthe invention. Accordingly, the foregoing description and drawings areby way of example only, and the scope of the invention should bedetermined from proper construction of the appended claims, and theirequivalents.

What is claimed is:
 1. A sensor security detector tape for wrappingaround an object to be protected, comprising: a material strip having apredetermined width and a predetermined length and first and secondends; a plurality of separate and parallel signal paths arranged alongthe predetermined length of the material strip, each signal path havinga first end and a second end and operative in a non-alarm condition toconduct a signal; a first circuit coupled to each first end of theplurality of signal paths and cooperative to couple signals from asignal source for continuous conduction over each of the plurality ofsignal paths; and a second circuit coupled to each second end of theplurality of signal paths for receipt of the plurality of signalsconducted over the plurality of signal paths and operative to provide analarm signal in the event of a break in any of the plurality of signalpaths and consequent loss of continuous conduction; wherein the secondcircuit includes an AND gate for receiving the signals from theplurality of signal paths, and a processor providing the alarm signal inthe event of the loss of continuous conduction of signals in one or moreof the plurality of signal paths.
 2. The sensor security detector tapeof claim 1, wherein the first circuit includes a multiplexer forcoupling a signal from a signal source to each of the plurality ofsignal paths.
 3. The sensor security detector tape of claim 1, whereineach of the signal paths is an optical fiber for carrying opticalsignals.
 4. The sensor security detector tape of claim 1, wherein thematerial strip is a fabric and each of the signal paths is woven intothe fabric.
 5. The sensor security detector tape of claim 1, furthercomprising: a layer of adhesive material disposed on a first surface ofthe material strip, wherein each of the signal paths is disposed in theadhesive material layer.
 6. The sensor security detector tape of claim5, further comprising: a releasable material layer disposed over theadhesive material layer.
 7. The sensor security detector tape of claim1, further comprising: a first flexible protection layer disposed on afirst side of the material strip; and a second flexible protection layerdisposed on the second side of the material strip.
 8. The sensorsecurity tape of claim 1, wherein each of the signal paths are retainedon a surface of the material strip.
 9. The sensor security detector tapeof claim 8 further comprising a flexible protection layer disposed overthe plurality of separate and parallel signal paths.
 10. The sensorsecurity detector tape of claim 1 wherein the sensor security detectortape is composed of a plurality of interconnected segments each havingthe material strip and the plurality of separate and parallel signalpaths; and wherein the processor of the second circuit provides a signalidentifying the particular material strip in which a break in any of theplurality of signal paths of that strip has occurred.